This invention relates to a shorting plug for selectively interconnecting contacts of an integrated circuit socket, and more particularly, a universally programmable shorting plug for establishing any desired electrical path or paths between the several contacts of the integrated circuit socket.
Miniturized circuits have been in use for some time and are employed on a ever-increasing scale in complex electronic equipment. The practices in the technology have evolved such that is is now common practice to use what has become known as integrated circuits, or physically small units containing an entire circuit (rather than a single electrical terminal), and to mount these integrated circuit packs or units to printed circuit boards and the like. It was early practice to solder the electrical contacts or terminals of these integrated circuits directly to points on the integrated circuit boards. In other cases, the electronic packs were mounted directly to a dielectric board with terminals extending through the board for connection to other conductors.
Through a gradual evolutionary use of these techniques, it is now more common and desirable to mount electronic integrated circuit units to a terminal board or printed circuit board for easy removal and easy exchanging of individual units. Accordingly, sockets are now often provided for receiving the pins (contacts) of the integrated circuit pack. These sockets generally include a dielectric housing supporting electrical contacts for receiving the pins of the integrated circuit packs, the contacts having long pins, or posts, extending from the lower part of the housing for insertion through holes in the printed circuit board. When the socket is mounted in place on the circuit board, the terminal post extends to the backside of the printed circuit board, providing posts for receiving a wrapped wire or other common type of conductor connection for joining the integrated circuit to other components on the same or other circuit boards.
During the assembly of a printed circuit board including sockets and integrated circuit packs, it is often desirable to conduct preliminary tests. For certain tests it is often necessary to effect the shorting of certain contacts of the various sockets in the circuit board assembly. Realizing the size of the miniturized elements in a circuit board, it is apparent that a single shorting plug for interconnecting only two contacts of an integrated socket is of very small size, and not readily manually manipulated. Furthermore, when the shorting plug is removed, and placed at a location near the technician's station, it often happens that the shorting plug becomes dirty, misplaced, etc. In order to overcome the deficiences of prior art shorting plugs utilized for interconnecting two contacts of an integrated circuit socket, applicant has developed the new and improved shorting plug which is the subject matter of U.S. Pat. No. 3,905,667 which issued on Sept. 16, 1975 to David J. Crimmins and William Y. Sinclair and is assigned to the assignee of the subject application, and is entitled "SHORTING PLUG FOR AN INTEGRATED CIRCUIT SOCKET".
For those preliminary tests wherein it is necessary to effect the shorting of numerous contacts of the various sockets to establish any desired electrical path or paths in the circuit board assembly, it has heretofore been the practice in the industry to solder discrete wires to the several contacts of the integrated circuit socket. Again realizing the minturized construction of the integrated circuit socket, the technique of soldering wires is a complicated procedure, is costly because of the time consumed in the hand wiring operation, and because of the miniturization possibly results in open circuits, thereby affecting the electrical test results.
Of course, as indicated above, although the shorting plug of U.S. Pat. No. 3,905,667 may be efficiently employed in applications wherein it is desired to interconnect only two, usually opposed, contacts, it is apparent that in those preliminary tests wherein it is required to effect multiple shorting between three or more contacts, or between contacts which are not in opposed relationship, the shorting plug of the prior art cannot be effectively employed. Thus, as indicated above, the industry has resorted to the technique of soldering wires, thereby resulting in a costly, inefficient, and unreliable interconnect arrangement.
Accordingly, there are several attributes considered desireable in a shorting plug for an integrated circuit socket including: providing a device which is universally programmable to achieve any desired electrical path or paths required for the testing of the circuit board assembly; means for effecting in an inexpensive manner the desired programming of the shorting plug to achieve the desired electrical path or paths; and a shorting plug which is relatively inexpensive to manufacture and results in a reliable shorting plug for test applications. It is an object of the present invention to provide all of these attributes in a single universally programmable shorting plug, and to this end, to abviate the shortcomings of the prior art devices to satisfy one or more of these requirements.